Number of the records: 1
Polar modes in K.sub.0.5./sub.Na.sub.0.5./sub.NbO.sub.3./sub. ceramics
- 1.
SYSNO ASEP 0331750 Document Type J - Journal Article R&D Document Type Journal Article Subsidiary J Článek ve WOS Title Polar modes in K0.5Na0.5NbO3 ceramics Title Polárni módy v keramické K0.5Na0.5NbO3. Author(s) Buixaderas, Elena (FZU-D) RID, ORCID
Nuzhnyy, Dmitry (FZU-D) RID, ORCID
Gregora, Ivan (FZU-D) RID, ORCID
Kamba, Stanislav (FZU-D) RID, ORCID, SAI
Malič, B. (SI)
Kosec, M. (SI)Source Title Ferroelectrics. - : Taylor & Francis - ISSN 0015-0193
Roč. 391, č. 1 (2009), s. 51-57Number of pages 7 s. Language eng - English Country GB - United Kingdom Keywords ferroelectrics ; lattice dynamics ; phonons ; Ir and Raman spectroscopy ; piezoelectrics ; THz spectroscopy Subject RIV BM - Solid Matter Physics ; Magnetism R&D Projects IAA100100701 GA AV ČR - Academy of Sciences of the Czech Republic (AV ČR) KAN301370701 GA AV ČR - Academy of Sciences of the Czech Republic (AV ČR) GA202/06/0411 GA ČR - Czech Science Foundation (CSF) CEZ AV0Z10100520 - FZU-D (2005-2011) UT WOS 000272607100008 DOI 10.1080/00150190903001177 Annotation Phonons in K0.5Na0.5NbO3 (KNN-50) ceramics were investigated from 10 to 900 K by means of Raman, infrared and THz spectroscopy. A first-order phase transition was detected from cubic to tetragonal phases at about 710 K, when the first component of the polarization appears. Transition from the tetragonal to the orthorhombic phase takes place around 475 K. The last transition from orthorhombic to rhombohedral phases is strongly first order. Tc is about 90 K and all Raman active modes below 100 cm-1 disappear. An overdamped soft mode is present at high temperatures in the THz range but another excitation below phonons is needed to explain the static value of the permittivity. Workplace Institute of Physics Contact Kristina Potocká, potocka@fzu.cz, Tel.: 220 318 579 Year of Publishing 2010
Number of the records: 1